Part in a ventilation system



FIG. 1 is a perspective view of a part in a ventilation system showing my new design;

FIG. 2 is a perspective view thereof; and,

FIG. 3 is a right side elevational view thereof.

The component shown with broken lines is not considered to be a part of the claimed design. 

The ornamental design for part in a ventilation system, as shown and described. 